1. Field of the Invention
The invention relates to a heat dissipation fan, and more particularly to a heat dissipation fan with improved efficiency.
2. Description of the Related Art
Currently, with increased heat generation in electronic elements, conventional convection methods are unable to dissipate heat sufficiently. Thus, heat dissipation fans are required.
Conventional heat dissipation fans provide dissipation efficiency of about 15˜30%. However, this efficiency is too low. Additionally, conventional heat dissipation fans generate additional heat into the system, thereby decreasing dissipation efficiency thereof. A high-power heat dissipation fan is thus required, and more energy is in turn wasted.
FIG. 1 shows a conventional fan, including a housing 10, a motor 12, a base 15 and a rotor. The base 15 is connected to the housing 10 via ribs 14 to support the motor 12. Conventionally, the heat of the fan is dissipated via an exposed metal shell 11 of the rotor. However, when the volume of the motor 12 decreases, the heat cannot be sufficiently dissipated.
Additionally, in theory, blades 13 of the rotor can provide dissipation efficiency of about 75˜85%. However, conventional heat dissipation fans only provide the total dissipation efficiency of about 15˜30%. Eliminating efficiency loss of the motor, in practice, blades 13 only provide dissipation efficiency of about 20˜45%. Thus, conventional heat dissipation fans must be modified to achieve improved dissipation efficiency.